2D Fluorinated Graphene Oxide (FGO)-Polyethyleneimine (PEI) Based 3D Porous Nanoplatform for Effective Removal of Forever Toxic Chemicals, Pharmaceutical Toxins, and Waterborne Pathogens from Environmental Water Samples.

Although water is essential for life, as per the United Nations, around 2 billion people in this world lack access to safely managed drinking water services at home. Herein we report the development of a two-dimensional (2D) fluorinated graphene oxide (FGO) and polyethylenimine (PEI) based three-dimensional (3D) porous nanoplatform for the effective removal of polyfluoroalkyl substances (PFAS), pharmaceutical toxins, and waterborne pathogens from contaminated water. Experimental data show that the FGO-PEI based nanoplatform has an estimated adsorption capacity (qm) of ∼219 mg g-1 for perfluorononanoic acid (PFNA) and can be used for 99% removal of several short- and long-chain PFAS. A comparative PFNA capturing study using different types of nanoplatforms indicates that the qm value is in the order FGO-PEI > FGO > GO-PEI, which indicates that fluorophilic, electrostatic, and hydrophobic interactions play important roles for the removal of PFAS. Reported data show that the FGO-PEI based nanoplatform has a capability for 100% removal of moxifloxacin antibiotics with an estimated qm of ∼299 mg g-1. Furthermore, because the pore size of the nanoplatform is much smaller than the size of pathogens, it has a capability for 100% removal of Salmonella and Escherichia coli from water. Moreover, reported data show around 96% removal of PFAS, pharmaceutical toxins, and pathogens simultaneously from spiked river, lake, and tap water samples using the nanoplatform.

Multi-Color-Emissive Magneto-Luminescent Nanoarchitectures for Targeted Identification of Heterogeneous Exosomes Associated with Lung Cancer Metastasis.

Due to the lack of early detection before metastasis and failure of current therapy to cure the disease, lung cancer contributes to the highest cancer-related mortality worldwide. Tenascin C (TNC) (+) exosomes promote metastasis, amphiregulin (AREG) (+) exosomes are associated with chemotherapy resistance, and programmed cell death ligand-1 (PDL-1) (+) exosomes are associated with immunotherapy resistance, and they are emerging as biomarkers in clinics. However, due to heterogeneity, rapid isolation and multiplex detection of these exosomes are challenging. Herein, we report the design of an antibody-conjugated multi-color (orange, yellow, and green)-emissive carbon dot (CD)-attached cobalt spinel ferrite (CoFe2O4)-based magneto-luminescent nanoarchitecture for targeted capturing and identification of TNC (+), AREG (+), and PDL-1(+) exosomes selectively and simultaneously from whole blood samples. More importantly, to capture and identify the targeted AREG (+) exosome from an infected whole-blood sample, an anti-AREG antibody-attached green (520 nm)-emissive CD-conjugated CoFe2O4 nanoparticle-based magnetic-green luminescence nanoarchitecture was developed. Similarly, an anti-PDL-1 antibody-attached orange (600 nm)-emissive CDs-based magnetic-orange luminescence nanoarchitecture has been produced to capture and identify the PDL-1 (+) exosome. Furthermore, an anti-TNC antibody-attached yellow (560 nm)-emissive CD-based magnetic-orange luminescent nanoarchitecture has been designed to capture and identify the TNC (+) exosome. Notably, our finding reveals that 100% TNC (+) exosomes can be captured and imaged selectively from an infected blood sample using an anti-TNC antibody-conjugated nanoarchitecture. In addition, 100% AREG (+) exosomes can be captured and imaged selectively using an anti-AREG antibody-conjugated nanoarchitecture. Moreover, 100% PDL-1 (+) exosomes can be captured and imaged selectively using an anti-PDL-1 antibody-conjugated nanoarchitecture. Furthermore, we have demonstrated that a multi-color-emissive nanoarchitecture can be used for capturing and imaging all three exosomes simultaneously.

Light-Induced Wavelength Dependent Self Assembly Process for Targeted Synthesis of Phase Stable 1D Nanobelts and 2D Nanoplatelets of CsPbI3 Perovskites.

Despite black cubic phase α-CsPbI3 nanocrystals having an ideal bandgap of 1.73 eV for optoelectronic applications, the phase transition from α-CsPbI3 to non-perovskite yellow δ-CsPbI3 phase at room temperature remains a major obstacle for commercial applications. Since γ-CsPbI3 is thermodynamically stable with a bandgap of 1.75 eV, which has great potential for photovoltaic applications, herein we report a conceptually new method for the targeted design of phase stable and near unity photoluminescence quantum yield (PLQY) two-dimensional (2D) γ-CsPbI3 nanoplatelets (NPLs) and one-dimensional (1D) γ-CsPbI3 nanobelts (NBs) by wavelength dependent light-induced assembly of CsPbI3 cubic nanocrystals. This article demonstrates for the first time that by varying the excitation wavelengths, one can design air stable desired 2D nanoplatelets or 1D nanobelts selectively. Our experimental finding indicates that 532 nm green light-driven self-assembly produces phase stable and highly luminescent γ-CsPbI3 NBs from CsPbI3 nanocrystals. Moreover, we show that a 670 nm red light-driven self-assembly process produces stable and near unity PLQY γ-CsPbI3 NPLs. Systematic time-dependent microscopy and spectroscopy studies on the morphological evolution indicates that the electromagnetic field of light triggered the desorption of surface ligands from the nanocrystal surface and transformation of crystallographic phase from α to γ. Detached ligands played an important role in determining the morphologies of final structures of NBs and NPLs from nanocrystals via oriented attachment along the [110] direction initially and then the [001] direction. In addition, XRD and fluorescence imaging data indicates that both NBs and NPLs exhibit phase stability for more than 60 days in ambient conditions, whereas the cubic phase α-CsPbI3 nanocrystals are not stable for even 3 days. The reported light driven synthesis provides a simple and versatile approach to obtain phase pure CsPbI3 for possible optoelectronic applications.

WO3 Nanowire-Attached Reduced Graphene Oxide-Based 1D-2D Heterostructures for Near-Infrared Light-Driven Synergistic Photocatalytic and Photothermal Inactivation of Multidrug-Resistant Superbugs.

The rapid emergence of superbugs which are resistant to existing antibiotics is becoming a huge global threat to public health, which demands the discovery of next-generation antibacterial agents for combating superbugs. Herein, we report the design of a two-dimensional (2D) reduced graphene oxide (r-GO) and one-dimensional (1D) WO3 nanowire-based photothermal-photocatalytic heterostructure for combating multiantibiotic-resistant Salmonella DT104, carbapenem-resistant Enterobacteriaceae Escherichia coli, and methicillin-resistant Staphylococcus aureus superbugs. In the presence of near-infrared (NIR) light, due to the generation of electrons and holes, the WO3-based heterostructure generates reactive oxygen species by photocatalytic reaction from water and oxygen, which kills superbugs. To enhance the photocatalytic superbug killing efficiency, r-GO has been used for suppressing the recombination of the photoinduced electron-hole pairs. Reported data show that NIR light-driven synergistic photocatalytic-photothermal processes can be used for 100% degradation of methylene blue using a heterostructure-based catalyst, and the photodegradation rate for the heterostructure is much better than the literature data for different types of WO3/GO-based nanocomposites. Experimentally, time-dependent antibacterial efficiency data reveals that the heterostructure can destroy 100% superbugs within 30 min of light exposure via a synergistic photothermal and photocatalytic mechanism, whereas the WO3 nanowire can kill around 35% superbugs only via photocatalytic action only and r-GO can kill 25% superbugs via photothermal action even after 30 min of exposure to light. Systematic time-dependent microscopy and spectroscopy studies reveal that the excellent antisuperbug activities for heterostructures are due to membrane damage, ATP, and DNA/RNA breakage. For possible real-life applications, sun light-based superbug inactivation shows 100% inactivation possible within 250 min of light exposure using 12 mg/mL heterostructures. The reported sun light-driven killing of superbugs provides a simple and versatile platform to combat drug-resistant superbugs.

"May the Force Be with You!" Force-Volume Mapping with Atomic Force Microscopy.

Information of the chemical, mechanical, and electrical properties of materials can be obtained using force volume mapping (FVM), a measurement mode of scanning probe microscopy (SPM). Protocols have been developed with FVM for a broad range of materials, including polymers, organic films, inorganic materials, and biological samples. Multiple force measurements are acquired with the FVM mode within a defined 3D volume of the sample to map interactions (i.e., chemical, electrical, or physical) between the probe and the sample. Forces of adhesion, elasticity, stiffness, deformation, chemical binding interactions, viscoelasticity, and electrical properties have all been mapped at the nanoscale with FVM. Subsequently, force maps can be correlated with features of topographic images for identifying certain chemical groups presented at a sample interface. The SPM tip can be coated to investigate-specific reactions; for example, biological interactions can be probed when the tip is coated with biomolecules such as for recognition of ligand-receptor pairs or antigen-antibody interactions. This review highlights the versatility and diverse measurement protocols that have emerged for studies applying FVM for the analysis of material properties at the nanoscale.

Water Triggered Synthesis of Highly Stable and Biocompatible 1D Nanowire, 2D Nanoplatelet, and 3D Nanocube CsPbBr3 Perovskites for Multicolor Two-Photon Cell Imaging.

Two-photon imaging in the near-infrared window holds huge promise for real life biological imaging due to the increased penetration depth. All-inorganic CsPbX3 nanocrystals with bright luminescence and broad spectral tunability are excellent smart probes for two-photon bioimaging. But, the poor stability in water is a well-documented issue for limiting their practical use. Herein, we present the development of specific antibody attached water-resistant one-dimensional (1D) CsPbBr3 nanowires, two-dimensional (2D) CsPbBr3 nanoplatelets, and three-dimensional (3D) CsPbBr3 nanocubes which can be used for selective and simultaneous two-photon imaging of heterogeneous breast cancer cells in the near IR biological window. The current manuscript reports the design of excellent photoluminescence quantum yield (PLQY), biocompatible and photostable 1D CsPbBr3 nanowires, 2D CsPbBr3 nanoplatelets, and 3D CsPbBr3 nanocubes through an interfacial conversion from zero-dimensional (0D) Cs4PbBr6 nanocrystals via a water triggered strategy. Reported data show that just by varying the amount of water, one can control the dimension of CsPbBr3 perovskite crystals. Time-dependent transition electron microscopy and emission spectra have been reported to find the possible pathway for the formation of 1D, 2D, and 3D CsPbBr3 nanocrystals from 0D Cs4PbBr6 nanocrystals. Biocompatible 1D, 2D, and 3D CsPbBr3 nanocrystals were developed by coating with amine-poly(ethylene glycol)-propionic acid. Experimental data show the water-driven design of 1D, 2D, and 3D CsPbBr3 nanocrystals exhibits strong single-photon PLQY of ∼66-88% as well as excellent two-photon absorption properties (σ2) of ∼8.3 × 105-7.1 × 104 GM. Furthermore, reported data show more than 86% of PL intensity remains for 1D, 2D, and 3D CsPbBr3 nanocrystals after 35 days under water, and they exhibit excellent photostability of keeping 99% PL intensity after 3 h under UV light. The current report demonstrates for the first time that antibody attached 1D and 2D perovskites have capability for simultaneous two-photon imaging of triple negative breast cancer cells and human epidermal growth factor receptor 2 positive breast cancer cells. CsPbBr3 nanocrystals exhibit very high two-photon absorption cross-section and good photostability in water, which are superior to those of commonly used organic probes (σ2 = 11 GM for fluorescein), and therefore, they have capability to be a better probe for bioimaging applications.

Mixed-Dimensional Heterostructure Material-Based SERS for Trace Level Identification of Breast Cancer-Derived Exosomes.

Raman spectroscopy has capability for fingerprint molecular identification with high sensitivity if weak Raman scattering signal can be enhanced by several orders of magnitudes. Herein, we report a heterostructure-based surface-enhanced Raman spectroscopy (SERS) platform using 2D graphene oxide (GO) and 0D plasmonic gold nanostar (GNS), with capability of Raman enhancement factor (EF) in the range of ∼1010 via light-matter and matter-matter interactions. The current manuscript reveals huge Raman enhancement for heterostructure materials occurring via both electromagnetic enhancement mechanism though plasmonic GNS nanoparticle (EF ∼107) and chemical enhancement mechanism through 2D-GO material (EF ∼102). Finite-difference time-domain (FDTD) simulation data and experimental investigation indicate that GNS allows light to be concentrated into nanoscale "hotspots" formed on the heterostructure surface, which significantly enhanced Raman efficiency via a plasmon-exciton light coupling process. Notably, we have shown that mixed-dimensional heterostructure-based SERS can be used for tracking of cancer-derived exosomes from triple-negative breast cancer and HER2(+) breast cancer with a limit of detection (LOD) of 3.8 × 102 exosomes/mL for TNBC-derived exosomes and 4.4 × 102 exosomes/mL for HER2(+) breast cancer-derived exosomes.

2D and Heterostructure Nanomaterial Based Strategies for Combating Drug-Resistant Bacteria.

In the last three decades, there has been a huge increase in the number of antibiotic-resistant bacterial strains, which is becoming a serious threat to public health. Since the discovery of new effective antibiotics has dramatically decreased in last ten years, there are huge initiatives to develop new antimicrobial approaches to fight drug-resistant bacterial infections. In the last decade, a new nanoparticle-based tool has emerged to combat deadly bacterial infections, which may overcome the barriers faced by antibiotic resistance. The current mini-review highlights recent reports on two-dimensional (2D) graphene oxide (GO), 2D transition metal dichalcogenides (TMD), 2D MXenes, and 2D heterostructure material-based approaches to tackle bacteria. Notably, we discuss the major design criteria which have been used to develop novel antimicrobial 2D and heterostructure materials to eliminate bacterial infections. Next, details on the various mechanisms underlying antibacterial activity for 2D and heterostructure materials such as physical/mechanical damage, lipid extraction, oxidative stress, and photothermal/photodynamic effects have been discussed. Finally, we highlight the promises, major challenges, and prospects of nanomaterial-based approaches to combat multidrug-resistant bacterial infections.

A WS2-gold nanoparticle heterostructure-based novel SERS platform for the rapid identification of antibiotic-resistant pathogens.

The emergence of antibiotic-resistant bacteria is the biggest threat to our society. The rapid discovery of drug resistant bacteria is very urgently needed to guide antibiotic treatment development. The current manuscript reports the design of a 2D-0D heterostructure-based surface enhanced Raman spectroscopy (SERS) platform, which has the capability for the rapid identification of the multidrug resistant strain of Salmonella DT104. Details of the synthesis and characterization of the heterostructure SERS platform using a two dimensional (2D) WS2 transition metal dichalcogenide (TMD) and zero dimensional (0D) plasmonic gold nanoparticles (GNPs) have been reported. The current manuscript reveals that the 2D-0D heterostructure-based SERS platform exhibits extremely high Raman enhancement capabilities. Using Rh-6G and 4-ATP probe molecules, we determined that the SERS sensitivity is in the range of ∼10-10 to 10-11 M, several orders of magnitude higher than 2D-TMD on its own (10-3 M) or 0D-GNPs on their own (∼10-6 to 10-7 M). Experimental and theoretical finite-difference time-domain (FDTD) simulation data indicate that the synergistic effect of an electromagnetic mechanism (EM) and a chemical mechanism (CM) on the heterostructure is responsible for the excellent SERS enhancement observed. Notably, the experimental data reported here show that the heterostructure-based SERS has the ability to separate a multidrug resistance strain from a normal strain of Salmonella by monitoring the antibiotic-pathogen interaction within 90 minutes, even at a concentration of 100 CFU mL-1.

Development of Human Host Defense Antimicrobial Peptide-Conjugated Biochar Nanocomposites for Combating Broad-Spectrum Superbugs.

Infectious diseases by multidrug-resistant superbugs, which cannot be cured using commercially available antibiotics, are the biggest threat for our society. Due to the lack of discovery of effective antibiotics in the last two decades, there is an urgent need for the design of new broad-spectrum antisuperbug biomaterials. Herein, we report the development of antisuperbug nanocomposites using human host defense antimicrobial peptide-conjugated biochar. To develop an economically viable technology, biochar, a carbon-rich material from naturally abundant resource, has been used. For combating broad-spectrum superbugs, a nanocomposite has been designed by combining biochar with α-defensin human neutrophil peptide-1 (HNP-1), human ß-defensin-1 (hBD-1), and human cathelicidin LL-37 antimicrobial peptide. The designed three-dimensional (3D) nanocomposites with pore size between 200 and 400 nm have been used as channels for water passage and captured superbugs. The reported data demonstrated that antimicrobial nanocomposite can be used for efficient capture and eradication of Gram-negative carbapenem-resistant Enterobacteriaceae (CRE) Escherichia coli (E. coli) and Klebsiella pneumoniae (KPN) superbugs, as well as Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) superbugs. Possible mechanisms for broad-spectrum antisuperbug activities using hydrogel have been discussed.

Designing Highly Crystalline Multifunctional Multicolor Luminescence Nanosystem for Tracking Breast Cancer Heterogeneity.

Breast tumor heterogeneity is responsible for the death of ~ 40,000 women in 2017 in USA. Triple-negative breast cancers (TNBCs) are very aggressive and it is the only breast cancer subgroup still lacking effective therapeutic. As a result, early stage detection of TNBC is vital and it will have huge significant in the clinics. Driven by the need, here we report the design of highly crystalline antibody-conjugated multifunctional multicolor luminescence nanosystem derived from naturally available popular tropical fruits mango and prune, which have capability to track breast cancer heterogeneity via selective separation and accurate identification of TNBC and HER-2 (+) or ER/PR (+) breast cancer cells selectively and simultaneously. A detailed synthesis and characterization of multifunctional multicolor nanosystems from tropical fruits has been reported. Experimental results show that by changing the fruits, multicolor luminescent carbon dots (LCDs) can be developed and is mainly due to the formation of highly crystalline nano dots with different heavy metal doping and also due to the presence of different types of surface functional groups. Experimental data presented show that multifunctional multicolor nanoprobe can be used for highly selective and simultaneous capturing of targeted TNBCs, HER2(+) or ER(+) breast cancer cells and the capture efficiency can be as high as 98%. Reported data indicate that multicolor fluorescence imaging can be used for mapping hetergenous breast cancer cells simultaneously, and it can distinguish targeted TNBCs from non-targeted HER-2 (+) or ER/PR (+) breast cancer. Our finding suggests excellent possibility of designing multicolor nanosystems from natural fruits for tracking cancer heterogeneity in clinics.

Giant Chemical and Excellent Synergistic Raman Enhancement from a 3D MoS2-x O x -Gold Nanoparticle Hybrid.

Raman spectroscopy fingerprinting features many technological applications. For this purpose, the weak Raman signals need to be boosted dramatically by surface-enhanced Raman spectroscopy (SERS), which provides immense Raman enhancement via plasmonic and chemical mechanisms (CM). In this manuscript, we reveal the giant chemical as well as extremely high SERS enhancement from a three-dimensional MoS2-x O x -gold nanoparticle (GNP) hybrid, which has capability for ultrasensitive label-free sensing of chemical and biological molecules. Notably, reported data show that the chemical enhancement for the MoS2-x O x surface is ∼105, which is comparable with the plasmonic enhancement factor (EF) by GNP. Reported data show that the total Raman EF is ∼1013 from the GNP-MoS2-x O x hybrid. Intriguingly, combined experimental and theoretical finite difference time domain stimulation modeling findings show that the synergistic effect of electromagnetic mechanism and CM is responsible for huge SERS enhancement. Experimental results demonstrate that a proposed hybrid SERS platform can be used for fingerprint sensing of different multiple drug resistance bacteria at 5 cfu/mL concentration. Importantly, the current manuscript provides a good strategy for manipulating the SERS sensitivity to 13 orders of magnitude, which is instrumental for next-generation technological applications of Raman spectroscopy.

Antimicrobial Peptide-Conjugated MoS2-Based Nanoplatform for Multimodal Synergistic Inactivation of Superbugs.

Development of new antibacterial therapeutic materials is becoming increasingly urgent due to the huge threat of superbugs, which are responsible for more than half of a million deaths each year in this world. Here, we report the development of a novel nanobiomaterial based on a melittin antimicrobial peptide (AMP)-attached transition metal dichalcogenide MoS2-based theranostic nanoplatform. The reported nanoplatform has a capability for targeted identification and synergistic inactivation of 100% multidrug-resistant superbugs by a combined photo thermal therapy (PTT), photodynamic therapy (PDT), and AMP process. A novel approach for the design of a melittin antimicrobial peptide-attached MoS2-based nanoplatform is reported, which emits a very bright and photo stable fluorescence. It also generates heat as well as reactive oxygen species (ROS) in the presence of 670 nm near-infrared light, which allows it to be used as a PTT and PDT agent. Due to the presence of AMP, multifunctional AMP exhibits a significantly improved antibacterial activity for superbugs via a multimodal synergistic killing mechanism. Reported data demonstrate that nanoplatforms are capable of identification of multidrug-resistant superbugs via luminescence imaging. Experimental results show that it is possible to kill only ∼45% of superbugs via a MoS2 nanoplatform based on PTT and PDT processes together. On the other hand, killing less than 10% of superbugs is possible using melittin antimicrobial peptide alone, whereas 100% of methicillin-resistant Staphylococcus aureus (MRSA), drug-resistant Escherichia coli (E. coli), and drug-resistant Klebsiella pneumoniae (KPN) superbugs can be killed using antimicrobial peptide-attached MoS2 QDs, via a synergistic killing mechanism. Mechanisms for possible synergistic killing of multidrug-resistant superbugs have been discussed.

Water-Soluble and Bright Luminescent Cesium-Lead-Bromide Perovskite Quantum Dot-Polymer Composites for Tumor-Derived Exosome Imaging.

Cesium-lead-halide perovskite quantum dots (PQDs) are a highly promising class of the next-generation optical material for bioimaging applications. Herein, we present a nanocomposite strategy for the design of water-soluble, highly luminescence CsPbBr3 PQD nanocomposites without modifying the crystal symmetry and photoluminescence (PL) property. Water-soluble PQDs are reproducibly synthesized via encapsulating CsPbBr3 PQDs with polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (PS-PEB-PS) and poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol (PEG-PPG-PEG). In the reported design, the polystyrene triblock polymers strongly interact with the hydrophobic parts of PQDs, and the water-soluble PEG moiety acts as a protection layer to effectively prevent degradation of PQDs in water. The outer shell PEG layer also helps to develop biocompatible PQDs. Reported data indicate that encapsulating CsPbBr3 PQDs with a polymer helps to improve the photoluminescence quantum yield (PLQY) from 83% to 88%, which may be due to a decrease in the surface defects after the effective polymer coating. Experimental data show that the PL intensity from CsPbBr3 PQD nanocomposites remains unchanged even after 30 days of exposure in air. Similarly, reported data indicate that nanocomposites retain their luminescence properties in water for the first 8 days and then decrease slowly to 60% of its initial PL intensity after one month. On the other hand, the PL emission for the PQD without polymer encapsulation is completely quenched within a few hours. Exosomes are a highly promising avenue for accessing tumor type and stage and monitoring cancer treatment response. Reported data reveal that anti-CD63 antibody-attached PQD nanocomposites are capable of tracking triple-negative MDA-MB-231 breast tumor-derived exosomes via binding using anti-CD63 antibody and selective green luminescence imaging using PQD nanocomposites.

Fluorescence Resonance Energy Transfer Based Highly Efficient Theranostic Nanoplatform for Two-Photon Bioimaging and Two-Photon Excited Photodynamic Therapy of Multiple Drug Resistance Bacteria.

Near-infrared (NIR) light between 700 and 2500 nm, which is in the range of the first, second, and third biological windows, has the capability to penetrate biological tissues and blood, which provides a huge advantages of higher penetration depth. However, because of the lack of available biocompatible single photon probes in NIR window, there is an urgent need for new theranostic material, which could be used for two-photon bioimaging as well as for two-photon photodynamic therapy (PDT) in biological window. Driven by the need, the current manuscript reports gold nanoclusters (GNCs) attached graphene quantum dot (GQD) based two-photon excited theranostic nanoplatform with high two-photon absorption, very strong two-photon luminescence, as well as two-photon stability in NIR region. Experimental result shows strong two-photon luminescence and two-photon-induced PDT, which is based on fluorescence resonance energy transfer (FRET) mechanism, where graphene quantum dots with very high two-photon absorption act as two-photon donors and gold nanoclusters act as acceptors. Reported data indicate that 1O2 generation efficiency enhances tremendously due to the FRET process, which increases the two-photon excited PDT efficiency for multiple drug resistance bacteria (MDRB). Reported data indicate that the nanoplatform has the capability for bright two-photon bioimaging and two-photon photodynamic therapy for MRSA and carbapenem-resistant (CRE) Escherichia coli. Reported nanoplatform is a promising candidate to serve as a contrast agent for multiphoton imaging as well as for two-photon excited PDT agent to eliminate multidrug-resistant strains.